Author Topic: Emulsion hardeners  (Read 1634 times)

Offline Rockers

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Emulsion hardeners
« on: September 24, 2014, 08:19:38 AM »
I`m especially interested in the Murakami ones. What are they offering and is there one that leaves you screen still recyclable in a short amount of time.


Offline Orion

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Re: Emulsion hardeners
« Reply #1 on: September 24, 2014, 08:24:11 AM »
Dale Hoyal

Offline Parker 1

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Re: Emulsion hardeners
« Reply #2 on: September 24, 2014, 09:42:45 AM »

Offline ABuffington

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Re: Emulsion hardeners
« Reply #3 on: September 24, 2014, 12:57:04 PM »
Murakami Hardeners for WB and Discharge,

If you use one of our SBQ emulsions, Aquasol HV, HVP, Photocure BLU, TXR the first step would be to add 8g diazo per gallon to increase water resistancy in a pure photopolymer emulsion.

Then you can use MS-Hardener which allows the screen to be reclaimed. Apply with a wet cloth or a paint roller dipped in hardener.  Dry in sun (for heat) or put in a screen drying cabinet at 100 degrees.  Heat helps the hardener do it's job.

If you want near permanent screens you can use A&B Hardeners.  Mix only what you will use in a 24 hour period with equal amounts of A&B.  Good for long runs and multi color discharge prints.   Reclaiming is not impossible just difficult.  You need to etch the surface with a caustic haze remover, HR-700 from us.  Leave on for 5 minutes then apply emulsions remover, or better use a concentrated dip tank of emulsion remover.  ER-605 7.5:1 mix.

For Dual Cures and Diazo based emulsions like SP-1400, SP-7500, Photocure PRO you can harden with MS Hardener for reclaiming, or A&B Hardener for stronger screens.

One note worth mentioning is the stencil strength is determined more by how well you expose it with good strong multi spectral light.  Hardeners assist strength, but shouldn't be looked at as the answer to making a good wb or discharge screen.  A screen shot on an 8k Douthitt will be far stronger than one shot on fluo tubes.   I may not even need to harden the screen on a 2,000-5,000 piece order with HVP if I have exposed it with quality light for the maximum amount of light possible.  Murakami emulsion is designed to be exposed completely and still develop details with a pressure washer.  Many shops have bad habits of under exposing a screen to get details due to emulsions that have to be underexposed to get details.  Applying hardener to an under exposed screen is just applying a band aid to a screen that has incomplete exposure.  The hardener affects the surface, not the entire thickness of the emulsion, only good exposure practices create cross linking that leads to a strong screen.  Pure Photopolymers do gain some strength in post exposure, but never as much strength as they can achieve with:  A well dried screen, complete exposure, MS or A&B Hardeners, Post expose in sun/exposure unit then dry in screen drying cabinet/room at 100 degrees will achieve an incredibly strong screen. 
« Last Edit: September 24, 2014, 05:22:58 PM by ABuffington »
Alan Buffington
Murakami Screen USA  - Technical Support and Sales
www.murakamiscreen.com

Offline kingscreen

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Re: Emulsion hardeners
« Reply #4 on: September 24, 2014, 03:24:19 PM »
We use CCI's. Reclaims with only a little extra soak time.
Scott Garnett
King Screen

Offline Rockers

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Re: Emulsion hardeners
« Reply #5 on: September 29, 2014, 09:17:56 PM »
This might sound like a stupid question but since I`m totally new to the use of hardeners do I apply it to both sides of the screen or just the squeegee or the print side?
If I get hardener in the image area that is going to be washed out after we dried the hardener?

 

Offline brandon

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Re: Emulsion hardeners
« Reply #6 on: September 29, 2014, 10:15:50 PM »
Go with what Al said above. A correctly exposed screen is your best bet. I learned a couple of years ago now hardeners are more like a band aid really 

Offline Evo

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Re: Emulsion hardeners
« Reply #7 on: September 29, 2014, 11:06:52 PM »
This might sound like a stupid question but since I`m totally new to the use of hardeners do I apply it to both sides of the screen or just the squeegee or the print side?
If I get hardener in the image area that is going to be washed out after we dried the hardener?

Both sides. Wet a rag, sponge or roller and go to town. Wet both sides and dry. The hardener will evaporate from the image area.
There is scarcely anything in the world that some man cannot make a little worse, and sell a little more cheaply. The person who buys on price alone is this man's lawful prey.
John Ruskin (1819 - 1900)

Offline Rockers

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Re: Emulsion hardeners
« Reply #8 on: September 29, 2014, 11:19:06 PM »
Cheers everyone. Appreciate the help.